Shielding and corrosion properties of the Alloy 709 as canister material for spent nuclear fuel dry casks

The shielding and corrosion properties of the Alloy 709 advanced austenitic stainless steel have been investigated as a candidate canister material in spent fuel dry casks. The results revealed that the experimental and computational data of the linear and mass attenuation coefficients of the alloy are in good agreement, in which the attenuation coefficient values decreased with increasing photon energy. Alloy 709 was shown to exhibit the highest linear attenuation coefficient against gamma rays when compared to 304 and 316 stainless steels. On the other hand, Alloy 709 exhibited no considerable weight change over a 69-day period in circulating salt brines corrosion testing, while it showed an exponential increase of corrosion current density with temperature in acidic and basic corrosive solutions during electrochemical polarization corrosion testing. Furthermore, Alloy 709 was the least corroded steel compared to other austenitic stainless steels in both acidic and basic solutions. The optimistic results of the shielding and corrosion properties of Alloy 709 due to its chemical composition, suggest utilizing it as a canister material in spent nuclear fuel dry casks.(c) 2022 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).